20982789 has 6 divisors (see below), whose sum is σ = 30308486. Its totient is φ = 13988520.

The previous prime is 20982779. The next prime is 20982791. The reversal of 20982789 is 98728902.

It can be written as a sum of positive squares in only one way, i.e., 13198689 + 7784100 = 3633^2 + 2790^2 .

It is not a de Polignac number, because 20982789 - 2⁵ = 20982757 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20982779) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1165702 + ... + 1165719.

Almost surely, 2^20982789 is an apocalyptic number.

It is an amenable number.

20982789 is a deficient number, since it is larger than the sum of its proper divisors (9325697).

20982789 is a wasteful number, since it uses less digits than its factorization.

20982789 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2331427 (or 2331424 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 45.

The square root of 20982789 is about 4580.6974359807. The cubic root of 20982789 is about 275.8170258571.

The spelling of 20982789 in words is "twenty million, nine hundred eighty-two thousand, seven hundred eighty-nine".